1. Field of the Invention
The present invention relates to an image processing apparatus having a function to store image data and a function to output the image data.
2. Description of the Prior Art
Such apparatus, hitherto, has included known facsimile apparatuses having a copy function or recording apparatuses of various kinds which can communicate with a host system or terminals.
Generally, such conventional apparatuses are constituted as shown in FIG. 1. In the apparatus shown in the diagram, an image of an original 1A is read by photoelectric converting means 1B such as a CCD sensor or the like, and either the image signal digitized by a binarization circuit 2 by way of a predetermined threshold value or the image signal returned as a binarized signal by a receiver circuit 5 and a decoder 6 through a line 7 is outputted to a printer 4 through an OR gate 3 in a real time manner.
Therefore, this kind of conventional apparatus has a drawback such that a communication cannot be performed through the line 7 during the copying operation.
On the other hand, recent facsimile apparatuses, have been provided with means for temporarily storing image signals representing more than one page of a standard document during the communicating operation in association with an increase in quantity of image signals which are transmitted or a reduction in costs of memory devices or in order to make the communication faster. With this apparatus, image data can be also received during the copying operation. However, in such an apparatus, no check is made to see if there is an error such as a transmission mistake or the like in the image data received and stored in the memory. Thus, there is a drawback such that erroneous data can be printed in the case where the received data is printed after completion of a copying operation.
In addition, in the early conventional facsimile apparatuses, transmission speed was low and the image signal included a relatively small quantity of data which is transmitted and received. Therefore, as shown in FIG. 8, the data received through a receiver circuit 11 from a communication line 14 such as a telephone line or the like is decoded in a real time manner through a decoder 12 by way of a decoding method in accordance with a predetermined coding system. The decoded result is recorded by way of a printer 13 such as a thermal recording apparatus, an ink jet recording apparatus, or the like. In such an arrangement, the image data received is always recorded by the printer 13, so that the receiving operation cannot be performed if no recording paper is set in the printer. Therefore, a facsimile apparatus having an image memory is considered. However, it is the present situation that image memories are mainly used to respectively coordinate the communicating speeds, decoding speeds of the decoder, and further the recording speeds of the recording output means, and they are not used as memories such that all of the image data received are preliminarily stored in the image memory such that this image data is recorded and outputted at a proper timing.